The present invention relates generally to shelters or protective buildings. More particularly, this invention pertains to a method and apparatus for a tornado shelter including a molded tub basin with anchored steel composite superstructure and landing deck.
Several United States Patents have been directed towards shelter structures. These include U.S. Pat. No. D 242,924, issued to McKnight on Jan. 4, 1977; U.S. Pat. No. 4,126,972, issued to Silen on Nov. 28, 1978; U.S. Pat. No. 4,336,674, issued to Weber on Jun. 29, 1982; U.S. Pat. No. 4,490,864, issued to Wicker, Jr. on Jan. 1, 1985; U.S. Pat. No. 4,539,780, issued to Rice on Sep. 10, 1985; U.S. Pat. No. 4,615,158, issued to Thornton on Oct. 7, 1986; U.S. Pat. No. 4,631,038, issued to Ritter et al. on Dec. 23, 1986; U.S. Pat. No. 4,779,294, issued to Miller on Oct. 25, 1988; U.S. Pat. No. 4,955,166, issued to Qualline et al. on Sep. 11, 1990; U.S. Pat. No. 5,376,315, issued to Fricke on Dec. 27, 1994; U.S. Pat. No. 5,481,837, issued to Minks, Jr. on Jan. 9, 1996; U.S. Pat. No. 5,724,774, issued to Rooney on Mar. 10, 1998; U.S. Pat. No. 5,829,208, issued to Townley on Nov. 3, 1998; U.S. Pat. No. 5,870,866, issued to Herndon on Feb. 16, 1999; U.S. Pat. No. 5,904,446, issued to Carlinsky et al. on May 18, 1999; and U.S. Pat. No. 5,930,961, issued to Beaudet on Aug. 3, 1999. A brief summary of the most pertinent of these patents is outlined in the following discussion.
U.S. Pat. No. 4,539,780, issued to Rice on Sep. 10, 1985, discloses a STORM CELLAR OR THE LIKE. This patent describes the insertion of a pre-cast molded concrete base into the ground as a base for an upper cast member. The upper and lower pre-cast sections are joined to form a completed storm cellar.
U.S. Pat. No. 4,615,158, issued to Thornton on Oct. 7, 1986, discloses a MOBILE HOME TORNADO SHELTER. The specification is directed towards a tornado shelter with the passageway connected to the interior of a mobile home.
U.S. Pat. No. 4,955,166, issued to Qualline et al. on Sep. 11, 1990, discloses a TORNADO UNDERGROUND SHELTER. This is a fiberglass unit that prefabricated and then transported for final constructed on site. The unit features an integral seat that is fabricated into the bottom surface and which also adds strength to the unit. In addition, the patent describes the use of the tornado shelter under a patio.
U.S. Pat. No. 5,481,837, issued to Minks, Jr. on Jan. 9, 1996, discloses a STORM SHELTER FOR USE WITH A MOBILE HOME. This patent describes the use of a shelter for a mobile home with the roof of the shelter forming a stoop for an entrance to the mobile home. The unit is constructed for prefabricated slabs of concrete that are bolted together on site.
None of this prior art discloses a protective shelter for installation above and in the ground including a superstructure style frame, a composite wall structure for absorbing energy from missile impacts, and a tub encased in a foundation. What is needed, then, is a improved method and apparatus for constructing a tornado shelter including a molded tub basin with anchored steel superstructure and landing deck.
A protective shelter for installation above and in the ground including a superstructure style frame, a composite wall structure for absorbing energy from missile impacts, and a tub encased in a foundation. The invention also discloses a method for constructing a protective shelter including a tub form and a superstructure which includes utilizing the availability of the tub form to provide a downward force such that the superstructure is not floated out of the excavation when the encasement is poured and removing the downward force after the concrete encasement has reached initial set stage. A further disclosure of the invention includes an energy absorbing compound wall structure for dissipating, transferring, and converting to potential energy the kinetic energy of a missile impact. This wall structure includes a support frame with an exterior wall panel bonded to the frame, a ribbed inside wall panel bonded to the exterior wall panel and the frame, and an energy dissipation block fixably positioned between the inside wall panel ribs and the frame.
In one of its exemplary forms, the present invention includes a protective shelter for installation above and in the ground which includes a superstructure including a top, a side, and a base connecting an above ground shelter portion and a below ground shelter portion. The above ground portion including a shelter roof deck supported on the top of the superstructure and a shelter wall attached to the side of the superstructure, and the below ground portion including a tub encased about the outside and underside with a concrete foundation encasement which secures the superstructure base in the ground and provides resistance against upward and lateral forces. This basic embodiment may include column legs secured in the concrete foundation encasement, wall top framing elements attached to the column legs, and wall bottom framing elements. A second embodiment may be constructed on a concrete slab with ground anchors as appropriate.
Further improvements to the basic structure of the shelter include encasement cross framing attached to the legs for supporting the tub and anchoring the superstructure in the encasement. This cross framing can be constructed using binders between the tube legs and tub supports spanning these binders to provide anchorage of the superstructure into the encasement, and also provide support and protection for the tub. Anchorage of the superstructure can be effectuated using leg base plates to provide anchorage into the encasement.
A shelter roof deck is taught which uses a concrete roof deck mounted on a ribbed panel with ribbed deck flutes and raised embossments for engaging the concrete roof deck. A wire reinforcing mesh is rigidly supported within the concrete roof deck at a distance between the ribbed deck flutes and the top of the wall top framing elements.
One important aspect of the present invention is the shelter wall that is constructed from a composite of materials including an exterior wall plate adhered to framing, an inside ribbed wall panel adhered to the exterior wall plate and the framing, and energy dissipation blocks adhered between the ribbed wall panel and the framing. This wall structure can include both ventilation systems and door hatches for access into the shelter. This structure teaches an energy-absorbing compound wall structure for taking the kinetic energy of a missile impact and dissipating, transferring, and converting the kinetic energy to potential energy. The potential energy is permanently or temporarily stored in the shelter walls for protecting objects stored in a protective area. The adhesive for bonding of the elements of the wall panels includes first, second, and third term strength properties which allow the adhesive to dissipate energy, transfer energy, hold energy within the wall structure, and release the temporarily stored potential energy in the wall after the objects have been removed from the protective area.
A further advantage of the present invention includes a water impervious tub to allow for the shelter to be employed in regions where the water table is close to the ground surface. The tub includes both vertical tub walls and horizontal surfaces to provide structural strength of the thin membrane form. These surfaces may be implemented as steps, tub seats, seat-backs, and a tub floor. The tub form includes a drain pipe and plug connected opening into a gravel drain for removing water from the tub.
The tub allows for an improved installation method for the structure including filling the tub with water to provide a downward force such that the superstructure is not floated out of the excavation when the encasement is poured, and removing the downward force after the concrete encasement has reached initial set stage.